Commit 0f6cc801 authored by Silvan Mosberger's avatar Silvan Mosberger
Browse files

lib.fileset.toSource: Improve error for unknown file types 

This does decrease performance unfortunately

Benchmarking expression toSource { root = ./.; fileset = ./.; }
Mean CPU time 0.103747 (σ = 0.012415) for 10 runs is 97.32181384964636% (σ = 16.34179537413021%) of the old value 0.106602 (σ = 0.0125571)
Statistic .envs.elements (205920) is 105.5842% (+10891) of the old value 195029
Statistic .gc.totalBytes (20247696) is 101.7495% (+348160) of the old value 19899536
Statistic .nrThunks (134824) is 108.7878% (+10891) of the old value 123933
Statistic .symbols.number (996) is 100.1005% (+1) of the old value 995
Statistic .values.number (275238) is 104.1199% (+10891) of the old value 264347
parent 88f736f8

lib/fileset/internal.nix

+30 −19
Original line number Diff line number Diff line
@@ -424,7 +424,7 @@ rec { 
      # Filter suited when there's some files

      # This can't be used for when there's no files, because the base directory is always included

      nonEmpty =

        path: _:

        path: type:

        let

          # Add a slash to the path string, turning "/foo" to "/foo/",

          # making sure to not have any false prefix matches below.
@@ -432,7 +432,8 @@ rec { 
          # but builtins.path doesn't call the filter function on the `path` argument itself,

          # meaning this function can never receive "/" as an argument

          pathSlash = path + "/";

        in



          include =

            # Same as `hasPrefix pathSlash baseString`, but more efficient.

            # With base /foo/bar we need to include /foo:

            # hasPrefix "/foo/" "/foo/bar/"
@@ -453,6 +454,16 @@ rec { 
              # == inTree [ "bar" "baz" ]

              inTree (split "/" (substring baseLength (-1) path));

        in

        # This relies on the fact that Nix only distinguishes path types "directory", "regular", "symlink" and "unknown",

        # so everything except "unknown" is allowed, seems reasonable to rely on that

        if include && type == "unknown" then

          throw ''

            lib.fileset.toSource: `fileset` contains a file that cannot be added to the store: ${path}

                This file is neither a regular file nor a symlink, the only file types supported by the Nix store.

                Therefore the file set cannot be added to the Nix store as is. Make sure to not include that file to avoid this error.''

        else

          include;

    in

    # Special case because the code below assumes that the _internalBase is always included in the result

    # which shouldn't be done when we have no files at all in the base

    # This also forces the tree before returning the filter, leads to earlier error messages

lib/fileset/tests.sh

+3 −1
Original line number Diff line number Diff line
@@ -356,7 +356,9 @@ rm -rf -- * 


# non-regular and non-symlink files cannot be added to the Nix store

mkfifo a

expectFailure 'toSource { root = ./.; fileset = ./a; }' 'file '\'"$work"'/a'\'' has an unsupported type'

expectFailure 'toSource { root = ./.; fileset = ./a; }' 'lib.fileset.toSource: `fileset` contains a file that cannot be added to the store: '"$work"'/a

\s*This file is neither a regular file nor a symlink, the only file types supported by the Nix store.

\s*Therefore the file set cannot be added to the Nix store as is. Make sure to not include that file to avoid this error.'

rm -rf -- *



# Path coercion only works for paths